Magnetic material.



R. A. FESSENDEN.

MAGNETIC MATERIAL.

APPLICATION FILED MAR. 14, 1908.

1,074,424, Patented Sept." 30, I913.

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BY m UNITED STATES ATENT oFmcE.

REGINALD A. FESSENDEN, 0F BRANT ROCK, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO SAMUEL M. KINTNER, OF PITTSBURGH, PENNSYLVANIA, AND HALSEY M. BARRETT, OF BLOOMFIELD, NEW JERSEY, RECEIVERS.

MAGNETIC MATERIAL.

To all whom it may concern:

Be it known that I, REGINALD A. FEssEN- DEN, a citizen of the United States, residing at Brant Rock, in. the State of Massachusetts, have invented certain new and useful Improvements in Magnetic Material, of which the following is a specification.

My invention relates particularly to structures of magnetic material such as the wire used in instruments like the Poulsen telegraphone, where varying magnetic conditions are impressed upon a relatively movable wire.

One of the objects of the invention is to so form such structures so as to better enable it to retain polar magnetism and generally to get more powerful effects, and to enable the use of a less amount of material, such as wire in recording.

In the accompanying drawing illustrating one form of the invention,-Figures 1 and 2 are longitudinal sections of a composite wire and Fig. 3 is a plan illustrating a convenient mode of manufacturing the intermittent surfaces on the composite wire.

In the telegraphone for example, a solid iron or steel'wire is passed through a magnetic field to have varying degrees of mag- I netism impressed'upon -it in the form of a sound record, which is either permanent, or when desired, the record may be obliterated by removing the magnetism. The wire now in use being solid does not concentrate or retain polar magnetism well. I have found that this and other difficulties may be overcome and other advantages gained, by form ing the material such as wire with a corrugated or grooved face, making what is practically a series of separate bars to be magnetizedf-For example, as shown-in Fig. l I maveattach to both sides of a copper strip 5, as by welding, two strips of steel or iron 4 and 6. One of these strips is then cut into .crossbars 7. The interstices may be filled with other material to present a smooth surface if desired.

In the form of Fig. 2 a strip of copper or copper-nickel alloy, or any other knownnon magnetic material may be welded or other- Specification of Letters Patent. Application filed March 14,1908. Serial No. 421,218.

Patented Sept. 30, 1913.

wise fixed on a soft iron strip 9 which is then cut into the form of crossbars 7 as before. That is, the magnetic portion of the wire is broken up into small parts which are found to retain a greater amount of magnetism than if the magnetic material were continuous. The magnetism thus being more definitely marked off and concentrated on the wire, a less amount of wire is necessary, it having been found that one foot of this wire will be suflicient to perform the functions of8 or 10 ft. of the solid wire heretofore on a carriage 13, the grooves 11 are cut in the faceof the wire at once, the carriage shifting sidewise through definite distances; or otherwise the bars could be moved. In some instances, the composite wire can be satisfactorily cut by scratching it across, and of course milling tools can be used where convenient.

By this construction, which of course is not limited to wires but may be employed in disks or any other form of structure, I obtain much more powerful effects, increasing the residual magnetism, and so get louder reproduction and a more permanent-record, as well as lessening the amount of wire necessary.

Having thus described my invention and illustrated itsuse, what I claim as new and desire to secure by Letters Patent, is the following:

1. A telegraphone wire comprising a continuous elongated base, and a series of separated magnetic bodies attached in a crosswise position thereon.

2. A wire comprising a continuous supporting base, and a non-continuous magnetic face composed of a series of uniformly shaped elongated bars.

3. A telegraphone wire having a crosswise corrugated magnetic face. v

4. A telegraphone wire composed of a non-magnetic base, and a magnetic surface thereon comprising a series of separate bars lying across the wire.

5. A magnetic wire having a non-mag- 5 netic metal base and a series of magnetic bars fixed cross-wise thereon with intervening spaces.-- f a In testimony whereof I have hereunto signed my name in the presence of the two subscribed witnesses.

REGINALD A. FESSENDEN.

Witnesses:

A. STEIN, Jr., JESSIE E. BENT. 

